/* atof.c
 * Author:
 *      sibuser
 */
/* convert input char value to double and ptint it */
#include <stdio.h>

double Atof(char* s)
{
    double val, power;
    int i, sign;
    
    for (i = 0; isspace(s[i]); ++i){
        ;
    }
    sign = (s[i] == '-') ? -1 : 1;
    if (sign == '+' || s[i] == '-'){
        ++i;
    }
    for (val = 0.0; isdigit(s[i]); ++i){
        val = 10.0 * val + (s[i] - '0');
    }
    if (s[i] == '.'){
        ++i;
    }
    for (power = 1.0; isdigit(s[i]); ++i){
            val = 10.0 * val + (s[i] - '0');
            power *= 10;
    }
    return sign * val / power;
}
    

int main(int argc, const char** argv)
{
    const int SIZE = 1000;
    char stroka[SIZE];
    int c;
    int i = 0;
    while ((c = getchar()) != EOF){
        stroka[i++] = c;
    }
    stroka[i] = '\0';
    printf("\n%g\n", Atof(stroka));
}
